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GrismG - The grating ruling density

Description:
This attribute holds the number of grating rulings per unit length. The unit of length used should be consistent with the units used for attributes GrismWaveR and GrismNRP. The default value is 0.0. (the appropriate value for a pure prism disperser with no grating).
Type:
Double precision.
Class Applicability:
GrismMap
All GrismMaps have this attribute.


next up previous 264
Next: GrismM - The interference order
Up: AST Attribute Descriptions
Previous: GrismEps - The angle between the normal and the dispersion plane

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council